SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09c9f103285a9e52945f0eaf79ef72cf755dc76360f8742154ca6ebf38c27e84' 
  AND token = 'M2DcwrezZlwi8TpVMHqmViORUKUT7MH+8UOlRAPqKBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}